Corrosion

A painted Art Deco figurine of a dancer with arms outstretched
holding her skirt, is made from plaster of paris with an iron rod
armature (3mm diameter) through the head, arms and into the skirt.
The iron has corroded cracking the plaster.  Advice would be
appreciated on how to prevent the corrosion process continuing.  To
recommend a dry environment would not necessarily work as the
figurine is privately owned.  Initial thoughts were to use an alkali
to raise the pH at the metal surface (an approach used in rebar
corrosion in concrete), but this could affect the paint layer.
Impregnation with passivators such as phosphoric acid will be
difficult as the plaster is so absorbant.  The same for
consolidants.  Would Vapour Phase Inhibitors work in this situation,
if so which one?

Professor Colin Pearson

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                 Conservation DistList Instance 10:100
                   Distributed: Monday, May 12, 1997
                       Message Id: cdl-10-100-006
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